Energy and power in circuits

What is power?

Power is the rate of energy transfer.

How do you work out the energy transfer?

Energy transferred = Power x Time

What are the 3 parts of the energy transfer calculation measured in?

Energy transfer = Joules (J) Power = Watts (W) Time = Seconds (s)

How can we find power?

Power is dependent on current, voltage and resistance. You can calculate the power by using the voltage and current in this equation -> Power = Voltage x Current. We already know that current is voltage divided by resistance so if you rearrange this for voltage and then substitute into the formula above you have another way to find power -> Power = Current^2 x Resistance or P = I^2R